Tractive type relay



May 21, 1935. J, F, MERKEL 2,002,476

TRACT I VE TYPE RELAY Filed July 24, 1931 2 Sheets-Sheet 1 BY yr.

May 21, 1935. .1. F. MERKEL TRACTIVE TYPE RELAY Filed July 24, 1931 2Sheets-Sheet 2 Battery :xtant of Contact wipe FIG-.3.

FIG. 4.

ratentea luay -1, 1563 UNITED STATES PATENT OFFICE TRACTIVE TYPE RELAYApplication July 24, 1931, Serial No. 552,906

2 Glalms.

This invention relates in general to relays adapted for railway use, andhas more particular reference to relays of the tractive type which areadapted to have associated therewith suitable magnetic blow-out meansfor are suppression.

Among the objects of this invention is to provide a tractive type relayand magnetic blow-out structure which is compact in design and rugged inconstruction with suitable articulated contact fingers that areparticularly adaptable for use with magnetic blow-outs for aresuppression.

Other objects, purposes and characteristic features of the presentinvention will be in part obvious from the accompanying drawings, and inpart pointed out as the description of the invention progresses.

In describing the invention in detail, reference will be made to theaccompanying drawings, in which similar reference characters refer tocorresponding parts throughout the several views, and in which;

Fig. 1 is a top view of a relay and magnetic blow-out structure arrangedand constructed as one embodiment of the present invention, with certainparts shown in section as viewed on section line i-i of Fig. 2;

Fig. 2 is a side elevational view of the embodiment of this inventionwith certain parts shown in section as viewed on section line 2-2 ofFig. 1;

Fig. 3 is a front elevational view of the embodiment of this invention;and

Fig. 4 is a graphic illustration of the operation of the embodiment ofthe present invention.

With reference to the accompanying drawings, the tractive type relay ofthe present invention is preferably provided in pairs and associatedwith a magnetic blow-out structure, as illustrated in Fig. 3, whererelays A and B are associated with a magnetic blow-out structure MB.These relays A and B and magnetic blow-out structure MB are preferablymounted on a vertical terminal board 5 suitably located and formed ofinsulating material.

The relays A and B are substantially identical so that the descriptionwill be given with more specific reference to relay A. With reference toFig. 2 of the accompanying drawings, relay A is shown as including twocore members 6 and l which are attached to a back strap 8 by suitablenuts threaded on extensions of the respective core members. Suitablecoils 9 and ID are mounted on the core members 6 and 1 respectively. TheU-shaped electro-magnetic structure thus formed is secured to terminalboard 5 by suitable nuts.

This electro-magnetlc structure has associated therewith an armature i iwhich is mounted upon an armature support member i2 suitably attached tothe core members 6 and 7. Although the armature II is shown in anattracted posi- 5 tion for convenience, it is normally biased to adeenergized position by a coil spring l3 which is mounted over athreaded rivet l4 and held in position by suitable nuts and cotter key.The armature H, when in an energized or attracted position, is heldagainst suitable residual pins located in recesses in the respectivecore members 6 and 1.

Although it is to be understood that any suitable tractive typeelectro-magnetic structure may be employed in place of the oneillustrated, the embodiment of this invention is shown as employing atractive type structure which is more completely described in my pendingapplication Ser. No. 545,402 filed June 9, 1931.

A contact support member I5 is attached to an insulated member if: bysuitable rivets, which member is in turn secured to the armature l i bysuitable rivets with an interventing insulated member i'i. Thisarrangement completely insulates the contact support member Hi from thearmature.

The contact finger ill is provided with an extension lS which passesthrough a suitable recess in the contact support member $5. This 30contact finger it is biased downwardly by a coil spring iii that ispassed over the extension i8- and secured in a tensioned' position by acotter key 20. The contact finger i8 is thus pivoted on a flat edgebearing, and biased toward a central or mid-position by two coil springsN which are mounted within cupped washers 22 over a guide member 23 onopposite sides of the contact finger l8. The guide member 23 has acentrally located shoulder 23 against which the inside cupped washers 22are biased. The guide member 23 is suitably riveted to the contactsupport member l5 at one end, while a cotter key 24 at its other end isprovided for retaining the coil spring 2i and the cupped washers 22 onthe left of the shoulder 23.

A terminal 25 is provided for attaching suitable lead wires to thecontact finger l8. Contact points 26 and 21 are mounted on the free endof the contact finger l8, and are adapted to make contact with front andback fixed contacts. These contact points 26 and 27 are preferably ofcoin silver or the like, and are in form a curved or semi-circular shapefor reasons to be pointed out hereinafter.

The magnetic blow-out structure MB is provided with a back spacer 30having suitable receases into which coil mountings 3| and 32 may befitted. The back spacer and coil mountings are preferably of mouldedbakelite.

The coil mountings 3| and 32 are moulded in substantially the same form,each being provided with a circular recess into which a coilr'nay enter.A lug bolt 34 is moulded to the coil mounting 3|, for example, so thatit may be suitably drilled and top threaded to receive a stud bolt 35which draws the coil mounting 3| into the recess provided in the backsupport 35 and against the terminal board 5. The lug bolt 34 is arrangedso that it may be suitably employed as a terminal post.

The coil mounting 3| is moulded with a recess to receive a contact framewhich is thin metal strips bent to conform with the surface of the coilmounting as well as having extending portions for gripping the fixedcontact 3'7 which is preferably of carbon impregnated with copper, butmay be any other suitable contact material.

' The contact frame is preferably formed in two parts, an upper part 36and a lower part 38. This frame, thus formed of two parts, is held inposition by threading a tap bolt 38 into a nut 39.

The coil 33 is placed within its recess in the coil mounting 3|. A coreas is located on the inside of the coil, with two pole pieces 6| and (12held in position against the opposite ends of the core 50 by a screw 43.These pole pieces (ii and 42 fit within grooves or depressions on theirrespective sides of the coil mounting 3i, so as to be held in anextending horizontal position and to be flush with the sides of the coilmounting. Two porcelain shields 35 and iii, each in the form of ashallow trough like member, are inserted on the inside of the polepieces ii and 62 respectively. The fixed contact 37 is suiiicientlynarrow to al-' low these porcelain shields t6 and ii to pass on eitherside thereof and come in contact with the coil mounting 3|. Thus, theporcelain shields 4B and 4'! are held in position by the contacts and bytheir respective pole pieces.

As above mentioned, the coil mountings 3| and 32 are constructed in alike manner, as well as having their respective coils, cores, polepieces, contacts, porcelain shields, and the like, mounted thereon in asimilar manner. These two units, so to speak, are mounted side by sidewith a stud bolt 59 located between them. This stud bolt 5|] has ashoulder portion 50 so that at one end of this bolt the back spacer 30and the terminal board 5 are tightened against the shoulder by suitablenuts; while the opposite end of this stud bolt 50, is employed to holdfront spacers 5| and 52 which are also tightened against the shoulder bysuitable nuts.

The front spacer 52 is a straight fiat piece of metal which serves tospace the inside porcelain shields of the respective units; while thefront spacer 5| is a flat piece of metal with its ends turned over inorder to secure the outer porcelain shields of the respective units. Thetwo units are also connected by a cross strip 53 (see Fig. 3) which issecured at one end by the tap bolt 38 and at its opposite end by a tapbolt 54, which is the counter part of the tap bolt 38. This crossmember, as well as mechanically connecting the two units, serves as anelectrical connection between the front contacts of the two units, sothat a suitable terminal 55 is provided at a central point on the crossmember.

Each of these units of the magnetic blow-out structure MB is providedwith a back contact in a similar manner. For example, a back contact 60is mounted between the two porcelain shields 46 and 41 by a suitablecontact frame. This contact frame comprises a fixed member 5| which isriveted to the front spacer 5|, a movable member 52 anda bolt 63 whichserves to draw the two members together, so as to tightly hold thecontact 6D in position by the extending portions of the members SI and62.

As the front spacer 5| is ,of conducting material and is connected tothe stud bolt 58, the back contacts of the two units are electrically aswell as mechanically connected. The stud bolt 50 acts as the terminalfor the two contacts.

With the mechanism and contact arrangement constructed as abovedescribed, suitable circuits may be completed between themovablecontacts and the fixed contacts. For example, one circuit can becompleted from the terminal 25 to the terminal on the stud bolt 50 whenthe relay is in a deenergized position; while another circuit may becompleted between the terminal 25 and the terminal 55 when the relay Ais energized. Also, the relay B can close two similar circuits betweenits movable contact terminal and its fixed contact terminals, it beingnoted that the fixed contact terminals are in common with those of therelay A.

The windings of the respective relays A and B may of course be connectedin control circuits as desired, while the coils of the blow-out unitsare preferably connected in such circuits as are controlled by themovable contacts of the respective relays, as disclosed, for example, inthe application of W. H. Hoppe et al., Ser. No. 478,758 filed August 12,1930. Such a circuit connection provides that the magnetic fluxnecessary to cause the magnetic blow-out to function is produced by thecurrent in the circuits which are controlled (see Fig. 4) On the otherhand, suitable separate energizing means may be provided for therespective blow-out coils.

In either case, the coils of the magnetic blowout should be connected inaccordance with the present invention, so as to produce a magnetic fluxwhich acts upon the current flowing in the circuit to be broken in amanner to cause the arc to move upward and away from the relaymechanism. With reference to Fig. 4, if the current is flowing from thecontact point 27 to the fixed contact 37, for example, when the relay Abecomes deenergized, then the coil 33 should be so energized as to causethe pole piece 4| to be a north pole and the pole piece 42 to be a southpole. This causes the arc formed upon the breaking or moving apart ofthe two contacts 21 and 31, to move upwardly and away from the relaymechanis'm. Similar connections and energization of the respectiveblow-out coils should be employed with respect to all of the contactsand the currents controlled by them.

When a movable contact is changed from one position to the other, thefinger being articulated, moves along the surface of the fixed contactcausing what is commonly known as contact wipe. With this arrangement,anyarc, which is formed, is initiated at a point on the fixed andmovable contacts that is not actually employed as a contasting surfacewhen the relay is in a full deenergized or energized position. Also, asthe arc is moved upward along the surface of the fixed contact and alongthe curved surface of the movable contact by the magnetic flux as aboveexplained,

the arc is lengthened and at the same time is moved away from the activecontacting surface of the contacts.

In other words, the arrangement of contacts and magnetic blow-out of thepresent invention provides that the breaking of the arc shall not burnthe actual or final contacting surface of the contact points. This isbecause the contact wipe movement is in one direction from the initialcontacting point, while the arc movement is in the opposite direction(see Fig. 4). This feature in the present embodiment is provided by anarticulated contact finger attached to an armature which is pivotallysupported on an axis parallel with the path of flux which is employed toblow out or break an arcing current at the associated contacts, it beingunderstood that the current in the circuit being opened has the relationto the magnetic flux as above pointed out.

Having described a relay mechanism and magnetic blow-out structureadapted for cooperation therewith, it is to be understood that theembodiment shown and described is merely illustrative of one specificembodiment of the invention; and it is to be understood that variousmodifications, adaptations, and additions may be made to this specificembodiment without departing from the spirit or scope of the invention,with the appended claims pointing out the novel features, andlimitations of the present invention, rather than the foregoingdescription thereof.

What I claim is:--

1. In combination, a terminal board, a back spacer and a front spacermounted on the terminal board, two separate units, and a single rodholding the units between said spacers, each unit comprising a moldedbakelite coil mounting, a coil within said mounting, a core within saidcoil, two pole pieces, one mounted on either end of said core, twospaced contacts mounted between said pole pieces, and twoporcelainshields for insulating said spaced contacts from the said pole piecesrespectively.

2. In combination, in a relay magnetic blow-out means, a panel, asocketed spacer having a plurality of spaced sockets therein, a unit foreach socket, each unit including a coil housing having a portion fittinginto a spacer socket, means for drawing and holding the housing in itssocket, a coil and core in the housing, a pole piece at each end of thecore extending away from the panel, spaced fixed contacts positionedbetween the pole pieces and insulated therefrom, a front spacer bearingagainst the units, and a rod passing through the front spacer andholding the front spacer and units against the said panel.

JOSEPH F. mm.

